replaced just guacd ( in pod )

[alexandruiancu]

I just swapped docker.io/guacamole/guacd:latest for ghcr.io/skylark-software/janua:latest in my guacamole pod ( recreated ) and cannot connect to a KDE desktop ( 3389 opened, app-org.kde.krdpserver.service running - Fedora, latest).
journalctl --user -ru app-org.kde.krdpserver.service

May 22 18:23:16 op krdpserver[122138]: [18:23:16:912] [122138:0001dd1a] [ERROR][com.freerdp.core.transport] - [transport_default_write]: BIO_should_retry returned an error: error:80000020:system library::Broken pipe
May 22 18:23:16 op krdpserver[122138]: [18:23:16:912] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [rdp_send_deactivate_all][0x55b28af254f0]: rdpMcs::userId == 0, skip sending PDU_TYPE_DEACTIVATE_ALL
May 22 18:23:16 op krdpserver[122138]: [18:23:16:912] [122138:0001dd1a] [ERROR][com.freerdp.core.transport] - [transport_default_write]: BIO_should_retry returned an error: error:80000020:system library::Broken pipe
May 22 18:23:16 op krdpserver[122138]: [18:23:16:912] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [rdp_send_deactivate_all][0x55b28af254f0]: rdpMcs::userId == 0, skip sending PDU_TYPE_DEACTIVATE_ALL
May 22 18:23:16 op krdpserver[122138]: [18:23:16:911] [122138:000209c3] [ERROR][com.freerdp.core.peer] - [transport_read_layer]: ERRCONNECT_CONNECT_TRANSPORT_FAILED [0x0002000D]
May 22 18:23:16 op krdpserver[122138]: [18:23:16:911] [122138:000209c3] [ERROR][com.freerdp.core.transport] - [transport_read_layer]: BIO_read returned a system error 104: Connection reset by peer
May 22 18:23:16 op krdpserver[122138]: [18:23:16:792] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x55b28af254f0]: *************************************************
May 22 18:23:16 op krdpserver[122138]: [18:23:16:792] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x55b28af254f0]: [experimental] build options might crash the application
May 22 18:23:16 op krdpserver[122138]: [18:23:16:792] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x55b28af254f0]: *
May 22 18:23:16 op krdpserver[122138]: [18:23:16:792] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x55b28af254f0]: * 'WITH_GFX_AV1=ON'
May 22 18:23:16 op krdpserver[122138]: [18:23:16:792] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x55b28af254f0]: This build is using [experimental] build options:
May 22 18:23:16 op krdpserver[122138]: [18:23:16:792] [122138:0001dd1a] [WARN][com.freerdp.core.rdp] - [log_build_warn][0x55b28af254f0]: *************************************************
May 22 18:16:20 op krdpserver[122138]: Failed to register with host portal QDBusError("org.freedesktop.portal.Error.Failed", "Could not register app ID: App info not found for 'org.kde.krdp-server'")
May 22 18:16:20 op krdpserver[122138]: Failed to register with host portal QDBusError("org.freedesktop.portal.Error.Failed", "Could not register app ID: App info not found for 'org.kde.krdp-server'")
May 22 18:16:19 op krdpserver[122138]: There are no outputs - creating placeholder screen
May 22 18:16:18 op systemd[118307]: Started app-org.kde.krdpserver.service - KRDP Server.
May 22 18:16:18 op systemd[118307]: Starting app-org.kde.krdpserver.service - KRDP Server...

any possible conflict between docker.io/guacamole/guacamole:latest and ghcr.io/skylark-software/janua:latest ?

[alexandruiancu]

The root cause seems to be the host system.

Inspecting guacd and ( host ) krdpserver logs found I'm missing libx264 codec ( included with nonfree ffmpeg - rpmfusion provides it for Fedora ).
After swapping free for nonfree ffmpeg, now I'm seeing:
krdpserver[32766]: DRM device not found

[bramej]

Thanks for following up with what you found — your diagnosis is right, and we were able to confirm it on our side.

On the original broken-pipe error: we reproduced your setup (janua guacd connecting to krdpserver on Fedora KDE) and could not reproduce the failure — the session established cleanly. The difference was exactly what you identified: our test host had RPM Fusion's nonfree ffmpeg with libx264. Fedora's default ffmpeg-free can't encode H.264, so krdpserver fails during GFX capability activation and the connection drops. That's a host configuration issue, not something in janua or guacd.

Two things worth confirming from our analysis while we were in there:

• Mixing images is fine. Swapping only guacd for janua-guacd under an upstream guacamole/guacamole web frontend is a supported configuration — both speak Guacamole protocol 1.6.0 over :4822, and the web tier is agnostic to which guacd backs it.
• AV1 was a red herring. Your krdpserver being built with WITH_GFX_AV1=ON didn't matter: when guacd doesn't advertise the FreeRDP AV1 capability, negotiation falls back to H.264/AVC gracefully. (That said, a FreeRDP 3.x update is in progress on our side.)

On DRM device not found: krdpserver wants /dev/dri/* for GPU-accelerated screen capture. The usual causes, in order of likelihood:

1. Headless or VM environment with no GPU (or no GPU passthrough) — there's simply no render node to open.
2. The user running krdpserver isn't in the render group — check ls -l /dev/dri/ and your group membership.
3. The Wayland session/compositor isn't exposing a DRM node to krdpserver.

If you're on real hardware with a working desktop, #2 is the first thing to check. If this is a VM, you'll need virtio-gpu or GPU passthrough for accelerated capture.

We'll add a Fedora/krdpserver troubleshooting section (libx264 + DRM) to the README so the next person doesn't have to dig for this. Leaving this open until that lands, then closing unless you're still seeing issues.